South Korea fires rounds at North in response to shell

By Ju-min Park and Tony Munroe SEOUL (Reuters) - South Korea said it fired tens of artillery rounds toward North Korea on Thursday after the North launched a shell toward a South Korean loudspeaker that had been blaring anti-Pyongyang broadcasts, as tension escalated on the peninsula. North Korea did not return fire but later warned Seoul in a letter that it would take military action if the South did not remove the loudspeakers within 48 hours, the South's defense ministry said. In the letter,